Acquired Dermal Macular Hyperpigmentation

Abstract

Acquired dermal macular hyperpigmentation (ADMH) is an umbrella term that includes disorders clinically characterized by small and large pigmented macules/patches and histopathologically showing an evidence of current or resolved interface dermatitis with pigment incontinence, without clinically significant prior inflammatory phase. The term intends to include diseases previously described in the literature as lichen planus pigmentosus, Riehl's melanosis/pigmented cosmetic dermatitis and ashy dermatosis/erythema dyschromicum perstans. The nomenclature and origin of these disorders have always been a matter of discussion. These disorders share many clinicopathological similarities, are difficult to treat and adversely affect the quality of life. Recent consensus points towards the need for a unifying term to facilitate research and therapeutic trials. This article aims to provide a comprehensive review of the recent advances in ADMH.

Pigmented contact dermatitis and hair dyes: A retrospective case–control multicentre study in Korea

“…Moreover, some chemicals implicated in PCD not only stimulate melanogenesis but are also known photosensitizers. 13 In our study, we explored sunscreen use in both the patient and control groups, but we found no significant difference in sunscreen use between the two groups. A more detailed history, including daily use patterns, such as amount of sunscreen agent and duration of wearing, is necessary to achieve meaningful results.…”

“…It is proposed that repetitive or persistent contact with low-level allergens induces cytolytic reactions, which is characterized by disruption of the basement membrane and pigment incontinence rather than frank eczematous reactions. 11,13,15 Even if subtle eczema develops, individuals with darker skin have difficulty noticing erythema or pigmentation, especially if there are no symptoms such as itching. Moreover, people often ignore mild symptoms and continue to use hair dyes for cosmetic reasons.…”

“…The pigmentation in PCD is usually more prominent laterally on the face rather than in the central area. 13 Recently, Bishnoi et al 9 reported that PCD on the ear helices and lobules was significantly more common in those with positive patch test results for hair colour products. In our study, the preauricular area and lateral cheeks (62.3%) were the most frequently involved sites, followed by the forehead or temple (51.2%), zygomatic area (49.0%), and mastoid area (posterior aspect of the ear, 44.3%).…”

“…The patients included in this study were diagnosed based on these characteristic pigmentations. The pigmentation in PCD is usually more prominent laterally on the face rather than in the central area 13 . Recently, Bishnoi et al 9 reported that PCD on the ear helices and lobules was significantly more common in those with positive patch test results for hair colour products.…”

Research Advances in the Treatment of Riehl’s Melanosis

“…What is noteworthy is that in an open-label pilot study, oral mycophenolate mofetil was initially applied in acquired dermal macular hyperpigmentation (ADMH), an umbrella term including RM. 19 , 20 Mycophenolate mofetil is one of immunomodulators, which can reduce immunosuppressive effect. It can reduce the hyperpigmentation through targeting the lymphocytes’ de-novo purine production pathway and probably inhibiting fibroblasts, which are also recognized with melanin contained.…”